A fraction is written in terms of two parts: the number on top is called the numerator and the number on the bottom is called the denominator. We can use the division method to solve this question. To get a decimal, simply divide the numerator 40 by the denominator 31:
40 (numerator) ÷ 31 (denominator) = 1.29
As a result, you get 1.29 as your answer when you convert 1 9/31 (or 40/31) to a decimal.